Table 2.
Descriptive Statistics on Secondary Efficacy Measures
| Buprenorphine Implant n=114 |
Placebo Implant n=54 |
Sublingual Buprenorphine n=119 |
P-Value Buprenorphine Implants vs. Placebo |
P-Value Buprenorphine Implant vs. Sublingual Buprenorphine |
|
|---|---|---|---|---|---|
| Urines Negative for Opioids, Weeks 1 to 24, meana | 36.0 | 14.4 | 35.1 | <.0001 | .81 |
| Urines Negative for Opioids, Weeks 1 to 16, meana | 39.6 | 17.9 | 37.8 | <.0001 | .65 |
| Urines Negative for Opioids, Weeks 17 to 24, meana | 28.9 | 7.2 | 29.6 | <.0001 | .86 |
| Proportion of Study Completers, N (%) | 73 (64.0) | 14 (25.9) | 76 (63.9) | .0002 | .62 |
| Clinical Opiate Withdrawal Scale (COWS) over 24 weeks, meanb | 2.49 | 4.52 | 1.71 | <.0001 | .0005 |
| Subjective Opiate Withdrawal Scale (SOWS) over 24 weeks, meanb | 5.30 | 8.42 | 2.83 | <.0001 | .0006 |
| VAS-opioid craving over 24 weeks, meanb | 10.2 | 21.8 | 7.1 | <.0001 | .054 |
| Patient Rated CGI-Improvement at week 24 (or endpoint),c N (%) | .031 | .30 | |||
| Very much improved | 47 (41.2) | 14 (25.9) | 57 (47.9) | ||
| Much improved | 35 (30.7) | 18 (33.3) | 29 (24.4) | ||
| Minimally improved | 10 (8.8) | 9 (16.7) | 9 (7.6) | ||
| No change | 3 (2.6) | 5 (9.3) | 0 | ||
| Minimally worse | 1 (0.9) | 1 (1.9) | 1 (0.8) | ||
| Much worse | 0 | 1 (1.9) | 0 | ||
| Very much worse | 0 | 0 | 0 | ||
| Clinician Rated CGI-Improvement at week 24 (or endpoint),c N (%) | .022 | .99 | |||
| Very much improved | 57 (50.0) | 12 (22.2) | 58 (48.7) | ||
| Much improved | 17 (14.9) | 8 (14.8) | 22 (18.5) | ||
| Minimally improved | 15 (13.2) | 11 (20.4) | 9 (7.6) | ||
| No change | 6 (5.3) | 10 (18.5) | 3 (2.5) | ||
| Minimally worse | 0 | 4 (7.4) | 1 (0.8) | ||
| Much worse | 0 | 1 (1.9) | 2 (1.7) | ||
| Very much worse | 0 | 1 (1.9) | 0 |
Significance tests for urine data based on analyses of variance with treatment, gender, and site in the model. Adjusted means presented.
Significance tests for COWS, SOWS, and VAS based on mixed-effects repeated measures analysis of variance using scores from week 1, 4, 8, 12, 16, 20, and 24, with treatment, week, treatment by week, baseline scores, gender, and site in the model.
Significance tests for Patient and Clinician CGI-Improvement scales based on CMH test stratified on gender and site. The COWS scale potentially ranges from 0 to 48, with 5–12 = mild, 13–24 = moderate, 25–36 = moderately severe, more than 36 = severe withdrawal. The SOWS scores potentially range from 0 to 64, with each of 16 questions rated on intensity of withdrawal on a 0 (not at all) to 4 (extremely) scale. The VAS scale ranges from 0 (no craving) to 100 mm (maximum experienced).